Ah, I see. Well, in that case, it sounds like the application may have had an update applied to it, or some items were added later. The way the uninstall feature works is it basically does a reverse install by using the index. So, if any items get modified or added to an application directory afterwards, the uninstall may end up leave those behind since they weren't part of the install index.
I've seen this happen when trying to uninstall Microsoft Office. If an Office update was installed after the original deployment, you can be left with a near empty Office directory in /Applications, with only a few items that were changed or added by the updater. You could try adding the updater into the uninstall process to see if it helps remove those last remaining items.
Also what I would do is check the index list on the package and compare it to the actual items in the application folder on disk. See if there are some additional items not included in the index. Also see if any updates were installed to that application.
As for the FEU and FUT options, I've never actually tried targeting those in an uninstall. I'm not sure if that actually works or not.
